This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The samples were transferred from their original containers with chloroform:methanol:water (2:1:0.1) into screw-cap tubes that were pre-rinsed with chloroform:methanol (1:1) and dried under a stream of nitrogen. The dried samples were crystallized into a MALDI plate with Trihydroxyacetophenone monohydrate (THAP) as matrix. Analysis of gangliosides present in the samples was performed in the negative ion mode by MALDI-TOF-MS using Bruker microflex.